Problem: A rectangle is $7$ inches long. The rectangle is also $3$ inches wide. What is its perimeter?
Answer: $7\text{ in}$ $3\text{ in}$ The perimeter is the total length of all the sides of the shape added together. Add up the lengths of the sides: $ \text{perimeter} = {3} + {7} + {3} + {7} $ $ \text{perimeter} = 20\text{ in} $